每一个DPU内均有一块实时数据库，实时数据库按站数和内外分成多块，每个站都用广播方式将自己的变量全量发送出去，同时每个站都会接收和更新其它站广播过来的全局变量，这样使每个站都可以实时的得到其它站的数据，从而使DCS可以很好的控制一个大系统。
DCS的控制器和HMI（人机界面）通常是合二为一的，这也比较适合大型过程控制的监控室，这使DCS更显示出浓厚的PC根源。
DCS的控制网络通常都是封闭的，通过一个历史数据库或者网关与外网交互，同时DCS对于工程师站、操作员站的定义比PLC工程体系要更为清晰和明显。
PLC：
小型微型PLC倒没什么冲突，因为结构和低成本的原因与其它两类产品完全不同。但中大型PLC因为大量使用PC_BASE技术使其与DCS和IPC+软逻辑基本上没有差别，只是因为这些厂商大多之前就是PLC厂商而且客户群都是PLC的客户，所以他的产品就叫PLC。
IPC+软逻辑：
在十几年前美欧的几个专家在这个问题有过一段很长时间的争论，围绕了一个问题是IPC+软逻辑如何实现才是合理的，因为当时主要有几种声音，一种是完全反对IPC在控制中的使用，因为显而易见的可靠问题，包括操作系统的兼容与可靠如何并重。另一种是完全支持IPC在工控中的应用，并认为要使用标准的PC软硬件，这样才可以使兼容和开放的优点充分体现。后一种是一种折中的方案，把PLC插入IPC内，做为IPC的一个板卡。在实现上面也有这么几种方案：
方案一：标准操作系统，包括WINNT（含XP、2000、NT等）、linux、DOS，加软逻辑软件
National Instruments 763061-03 GPIB X2 Cable – NEW
National Instruments NI PCMCIA GPIB Cable – 2 Meter
National Instruments FP-TC-120 8-Ch. Thermocouple Input
National Instrument PXI-5620 Frequency Domain Digitizer
National Instruments SCXI-1160 16-Channel Relay Board
National Instruments PCI-232/485, 2CH
National Instruments 777421L-04 Software for WIN NT/98
Field Point National Instruments # FP-A1-100
National instruments Matchmaker PCI RS-232, RS-484 Card
National Instruments. CB-27. Connector Block.
National Instruments 182869A-03 3 ft. SCSI To Parallel
National Instrument NI PCI-232/485 2CH 184686D-01
1.1 Meter National Instruments IEEE Cable 488
National Instrument PCI MIO 16XE-50 DAQ 183454F-01
National Instruments VXIpc-486 Model 566 182429M-20
National Instruments CARD PCI-6503 185183B-01 New
National Instruments NI-DAQ Data Aquisition Driver CD
National Instruments NI PCI-6528 Digital I/O 24 in/out
NATIONAL INSTRUMENTS GPIB-RS232 / GPIB-SERIAL CONVERTER
National Instruments GPIB-SCSI-A IEEE – SCSI Controller
Ukrainian national instrument SOPILKA flute 1950 C-tune
NI National Instruments PCMCIA-232/4
National Instruments PXI-8146RT system controller *wty
National Instruments SCXI-1302 REV:3.0, P/N 185163A-01
NATIONAL INSTRUMENTS 180524-02 0.2m 50-PIN RIBBON CABLE
National Instruments NI PXI-6031E DAQ Board
NEW NATIONAL INSTRUMENTS 763061-02 GPIB CABLE
National Instruments 777853-02 PCI-4851/2, 2-Port, Isol
National Instruments Relay Module SCXI-1000 SCXI-1160
National Instruments SCXI-1000 1200 Controller working
National Instruments. SCXI. RS485 / Parallel Adapter.
National Instruments 181638-01B National Instruments 18
NEW NATIONAL INSTRUMENTS 183064B-01 MODULE ER-8
National Instruments Type X2 763507-02 2.1 Meter
National Instruments 181830-01 AT-GPIB/TNT 181830 Card
National Instruments FP-1100 DeviceNet Interface
(Brand New / Used) NATIONAL INSTRUMENTS GPIB SOFTWARE
NATIONAL INSTRUMENTS NI PCI-DIO-96 CARD 182920D-01
National Instruments PXI-1010 8-Slot PXI/4 SCXI Chassis
National Instruments NI PXI-4060 5 1/2 PXI Multimeter
68 Pin MALE Breakout for National Instruments – USED
National Instruments NI PCI-5102 DAQScope 15MHz tested
Two National Instruments SH100-100 Cables
National Instruments Relay Module SCXI-1001 SCXI-1162HV
NATIONAL INSTRUMENTS PXI-5124 200 MS/s 12-Bit Digitizer
National Instruments NI PXI-6713 Analog Output PXI 6713
NATIONAL INSTRUMENTS 182920-01 NEW PCI-DIO-96
NATIONAL INSTRUMENTS IMAQ PCI-1422
NATIONAL INSTRUMENTS NI PCMCIA-GPIB #186736C-01 Tested
Rt Angle M DB37 Breakout w/BNC for National Instruments
National Instruments IEEE 488.2 GPIB with software
National Instruments PXI-8330 MXI-3 Interface for PCI
National Instruments AT-MIO-16E-10 board NI-DAQ 7 NEW
NATIONAL INSTRUMENTS NI PXI-8156B EMBEDDED CONTROLLER
National Instruments 777741-01 185030H-01 PCI-6713 NEW
NATIONAL INSTRUMENTS 4-AXIS STEPPER CONTROLLER / CABLES
National Instruments PXI-1045 18-Slot Chassis
National Instruments IMAQ PCI-1407 PCI Vision Card
National Instruments PCI-6032E 100 Ks/s 16-bit 16-ana
National Instruments SCXI-1540 8-channel LVDT Amplifier
National Instruments Data Acquisition Driver PCB & CD
National Instruments IEEE 488 GPIB Card P/N -181060-01
LOT – 8 National Instruments 776239-01 Relays – NIB
National Instruments. SH32-32-A. 5 mt Cable.
National Instruments MXI-4 Interface Module PXI-8331
